There are certain magic price and performance combinations that -- in the hands of specific companies -- tend to produce good to great speaker designs. For instance, Bose doesn't seem to be able to make a good iPod speaker for less than $300, but Logitech has made some great ones for $130 to $150. At certain price levels, these companies either refuse to release products or come out with ones that they know aren't exactly their finest work; the latter phenomenon pretty much explains Logitech's latest portable audio systems, S125i ($70) and S315i ($100). Both of these systems are budget-priced and less aggressively designed than the company's earlier, excellent Pure-Fi Anywhere series of speakers. We've decided to review them together, though they do have individual benefits and disadvantages worth noting separately.

The smaller, less expensive S125i looks a little alien from the front and kidney bean-like from the top, packing a couple of roughly 1.25” speakers into a semi-glossy black plastic casing with high-contrast white oval metal speaker grilles. S125i’s front has volume, power, and bass boost buttons, while its top has a Universal Dock well, and its back has ports for wall adapter power and auxiliary audio input. Logitech supplies a wall adapter for continuous run time, and has a white battery compartment on the bottom that lets the unit run for 10 hours off of four AA batteries, which aren’t included. It is designed solely for use with Dock Connecting iPods, not iPhones.

By comparison, the more expensive S315i is billed as “Rechargeable Speaker S315i,” possessing a substantially wider, matte black body that holds twin 2.5” speakers and a rechargeable battery. In an interesting design departure from the company’s earlier products, rubberized volume buttons are mounted on the unit’s back, as is a three-position power switch for Off, Power, and Efficient Power, along with a rubberized compartment for auxiliary audio and power connections. The system comes with a wall power adapter, and runs for 10 hours in standard Power mode, with a 20-hour run time in Efficient Power mode. It is designed to work with Dock Connecting iPods and iPhones alike.

At this point, if you’re familiar at all with Logitech’s earlier Pure-Fi Anywhere systems, you know that we’ve really loved and appreciated the sonic quality of these $130 to $150 units, which for that price included four total speakers—two active, two passive—plus 10-hour rechargeable batteries, carrying cases, and remote controls. Both of these newer systems drop speaker and sound quality, the remote controls, and the carrying cases to achieve their lower price points.

We found ourselves struggling to come up with a fair way to explain the sonic performance of S125i, which alternates from song to song between sounding good or only decent for the price. During some tracks, midrange distortion was so evident that we couldn’t get past it; during others, music sounded relatively smooth and well-matched to S125i’s equalization, and even benefitted from the bass-boosting button, which brought the low-end to levels we wouldn’t have expected from such tiny drivers. Yet one song later, the bass booster would need to be turned off because it was distorting the low end. “Inconsistent” would be the only way we could characterize this system’s sound; there are times when it sounds downright radio-like, and others when it’s cleaner and better. If it was always as good as it was at its best, or as bad as it was at its worst, it would be a lot easier to recommend or write off.

By comparison, S315i has a different set of performance characteristics. First, its dock doesn’t rely upon a recessed well, which initially made the unit impossible to use with certain encased iPhones and iPods; it does just fine with bare-bodied devices. Second, its power-efficient operation mode appears to be achieving its lower battery consumption by stripping out some of the frequencies in songs. When S315i is running in its standard power mode, capable of performing music at reasonable volumes for 10 hours, its sound is comparatively full-bodied but fairly flat: as with the S125i’s smaller drivers, the twin 2.5” speakers here are obviously being pushed to their limits to try and replicate as much of the audio spectrum as possible, and struggle a little with distortion throughout the range. Activate the power-conserving mode and the bass dips out, leaving even flatter, more radio-like sound. To be clear, the S315i’s audio is good enough to markedly upgrade the speakers found inside iPhones and iPod touches, offering dramatically higher volume and relatively midrange-focused audio with a little bass and a little treble to keeps things interesting, but it doesn’t produce the wows of a multi-driver audio system.

Though it’s not surprising that Logitech’s portable lineup gets better as you add $30 increments—the $130 Pure-Fi Anywhere 2 is superior to the $100 S315i, which is superior to the $70 S125i—the improvements are not linear. From our perspective, you get a lot better value from Pure-Fi Anywhere 2 than from the S315i, which is a just-recommendable audio system given its sonics and integrated battery, and both systems are smarter purchases than the S125i, which starts out weaker in audio and fluctuates enough in performance that we wouldn’t want to use it for much. If you’re considering a Logitech speaker purchase, focus on the Pure-Fi Anywhere 2 unless you’re willing to accept a bunch of compromises in order to achieve a lower price.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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